Small permanent magnetic particles properly surface coated are used to clean, polish, abrade or surface-coat the surfaces of larger objects by subjecting them to a rotating magnetic field as taught in U.S. Pat. No. 3,848,363. The rotating magnetic field is generated by a conventional AC electric motor stator which is wound with four or more overlapping coils arranged in a generally circular pattern of opposed pairs and that are energized with two or more out of phase sources of alternating current, so that opposed coils are in phase but of opposite magnetic polarity. The permanent magnetic particles and the objects to be treated are placed in a non-magnetic container which is placed in the rotating magnetic field. The magnetic particles under the influence of the rotating magnetic field become generally uniformly distributed in the container and each particle is caused to rotate on its axis and to revolve in an orbital path about the axis of the rotating field thereby to contact and surface treat all of the intricate surfaces of the objects in the container.
After the surface treatment in the rotating magnetic field is completed and the container is removed from the field, the magnetic particles are attracted to each other and conglomerate around the treated objects thereby making separation of the objects from the magnetic particles difficult. Prior to the present invention the surface treated objects have been separated from the magnetic particles by hand, a tedious and time consuming task.